What is Allfen CD (codeine and guaifenesin)?

Codeine is in a group of drugs called narcotics. It is a cough suppressant that affects the signals in the brain that trigger cough reflex.

Guaifenesin is an expectorant. It helps loosen congestion in your chest and throat, making it easier to cough out through your mouth.

The combination of codeine and guaifenesin is used to treat cough and to reduce chest congestion caused by upper respiratory infections or the common cold.

Codeine and guaifenesin will not treat a cough that is caused by smoking, asthma, or emphysema.

Codeine and guaifenesin may also be used for other purposes not listed in this medication guide.

What is the most important information I should know about Allfen CD (codeine and guaifenesin)?

Ask a doctor or pharmacist before using any other cough or cold medicine. Guaifenesin is contained in many combination medicines. Taking certain products together can cause you to get too much guaifenesin. Check the label to see if a medicine contains an guaifenesin, or an expectorant.

Codeine and guaifenesin may impair your thinking or reactions. Avoid driving or operating machinery until you know how this medicine will affect you.

Codeine may be habit-forming and should be used only by the person it was prescribed for. This medication should never be shared with another person, especially someone who has a history of drug abuse or addiction. Keep the medication in a secure place where others cannot get to it.

Do not give this medication to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.

What should I discuss with my healthcare provider before taking Allfen CD (codeine and guaifenesin)?

You should not take this medication if you are allergic to codeine or guaifenesin.

To make sure you can safely take codeine and guaifenesin, tell your doctor if you have any of these other conditions:

heart disease, heart rhythm disorder;

asthma, COPD, emphysema, or other breathing disorders;

a history of head injury or brain tumor;

epilepsy or other seizure disorder;

a stomach or intestinal disorder;

Addison's disease or other adrenal gland disorders;

curvature of the spine;

a thyroid disorder;

liver or kidney disease;

enlarged prostate; or

a history of depression, mental illness, or drug addiction;

FDA pregnancy category C. It is not known whether codeine and guaifenesin will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.

Codeine can pass into breast milk and may harm a nursing baby. The use of codeine by some nursing mothers may lead to life-threatening side effects in the baby. Do not use this medication if you are breast-feeding a baby.

Codeine may be habit forming and should be used only by the person it was prescribed for. Never share this medication with another person, especially someone with a history of drug abuse or addiction. Keep the medication in a place where others cannot get to it.

Older adults may be more likely to have side effects from this medication.

Liquid forms of this medication may contain sugar or artificial sweetener (phenylalanine). Talk to your doctor before using this form of codeine and guaifenesin if you have diabetes or phenylketonuria (PKU).

How should I take Allfen CD (codeine and guaifenesin)?

Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label. Cough or cold medicine is usually taken only for a short time until your symptoms clear up.

Do not give this medication to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.

Take codeine and guaifenesin with food if it upsets your stomach.

Drink extra fluids to help loosen the congestion and lubricate your throat while you are taking this medication.

Measure liquid medicine with a special dose-measuring spoon or cup, not a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

Call your doctor if your symptoms do not improve after 7 days of treatment, or if you also have a fever, headache, or skin rash.

This medication can cause unusual results with certain medical tests. Tell any doctor who treats you that you are using codeine and guaifenesin.

Do not stop using this medication suddenly after long-term use or you could have unpleasant withdrawal symptoms. Ask your doctor how to avoid withdrawal symptoms when you stop using the medication.

Store at room temperature away from moisture, heat, and light. Keep the bottle tightly closed when not in use.

Keep track of the amount of medicine used from each new bottle. Codeine is a drug of abuse and you should be aware if anyone is using your medicine improperly or without a prescription.

What happens if I miss a dose?

Since cough medicine is taken when needed, you may not be on a dosing schedule. If you are taking the medication regularly, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of codeine can be fatal.

What should I avoid while taking Allfen CD (codeine and guaifenesin)?

Codeine and guaifenesin may impair your thinking or reactions. Avoid driving or operating machinery until you know how this medicine will affect you.

Ask a doctor or pharmacist before using any other cough or cold medicine. Guaifenesin is contained in many combination medicines. Taking certain products together can cause you to get too much guaifenesin. Check the label to see if a medicine contains an guaifenesin, or an expectorant.

Drinking alcohol can increase certain side effects of codeine and guaifenesin.

Allfen CD (codeine and guaifenesin) side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop taking this medication and call your doctor at once if you have any of these serious side effects:

severe dizziness or drowsiness;

confusion, hallucinations, unusual thoughts or behavior;

urinating less than usual or not at all; or

slow heart rate, weak pulse, fainting, weak or shallow breathing.

Less serious side effects include:

dizziness, drowsiness, headache;

warmth, redness, or tingling under your skin;

nausea, vomiting, upset stomach;

constipation; or

skin rash or itching.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Allfen CD (codeine and guaifenesin)?

Before taking this medication, tell your doctor if you regularly use other medicines that make you sleepy (such as allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to sleepiness caused by codeine and guaifenesin.

This list is not complete and other drugs may interact with codeine and guaifenesin. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Professional resources

Other formulations

Related treatment guides

Where can I get more information?

Your pharmacist can provide more information about codeine and guaifenesin.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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